Electrical time switch



G. A. BURGESS ELECTRICAL TIME SWITCH June 26, 1928. 1,675,292

Filed June '2, 1926 2 Sheets$hest 1 June 26, 1928. 1,675,292

G. A. BURGESS ELECTRICAL TIME SWITCH Filed June 7, 1926 2 Sheets-$heat 2Inventor? Geo ye J47. fiagye fi, E W

Patented June 26, 1928.

UNITED STATES 1,675,292 PATErrr OFFICE.

GEORGE'A. BURGESS, OF WAUKEGAN, ILLINOIS, ASSIGNOR TO CHICAGO HARDWAREFOUNDRY COMIANY, OF NORTH CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

7 ELECTRICAL TIME SWITCH.

Application filed June 7,

This invention relates to that class of electrical time switchmechanisms, in which a closing of the circuit iseffected manually andthe opening of the circuit is effected automatically in a predeterminedperiod of time by operative connections with the motor of ablower orlike apparatus with which the switch mechanism is associated. And thepresent improvement has for its object:

To provide a structural formation and combination of the operative meansof a switch mechanism of the type above described with a revolving partof the apparatus with which it is associated, whereby the openingmovement of the switch mechanism is effected is attained in a certainand effective manner without liability of the mechanism failing tocomplete its full stroke or operation, and the consequent rendering theapparatus inoperative, all as will hereinafter more fully appear.

In the accompanying drawing i I Fig. 1, is a front elevation, with theen closing housing in section, of a hot air blast apparatusto which thepresent invention is applied. 7 w

Fig. 2, is an end elevation of the same with said housing also shown insection.

Fig. 3, a fragmentary sectional elevation of. the parts in a positiondifferent from that, shown in Fig. '2. 7 I Fig. 4, is a like fragment rysectional elevation showing the parts inanother different position. Y i

I Fig. 5, is a detail sectional elevation, show- "ing the operating. camofthe switch mechanism in. a different position from that shown in Figs.2, 3 and 4. Fig. 6,is a detail section of the operating cam andassociated parts, on line 6-6 Fig. 4.'

Like reference numerals indicate like parts in the different views.

In the". type of electrical switch mechanism employed in the presentinvention, the usual operating cam or wiper by which 1926. Serial No.114,058.

detail formation and arrangement of parts.

applied. to a hot air dryer for lavatory uses,

as follows The enclosing housing 1 with its outlet nozzle 2, andenclosed rotary air mover or fan 3, as well as the associated electricalair heating unit 4 and operating electric motor 5 are of any ordinaryconstruction and arrangement in use at this time in the type of hot airdriers above referred to.

The switch mechanism for opening and closing the electro-motive circuitto the motor 5 and electrical heating unit 4, is preferably of the snaptype and of any usual and suitable detail construction, preferably of aconstruction as follows The supporting plate 6 of the switch mechanismis fixedly secured in an upright position within the enclosing housing1, and carries near one end the pair of insulated stationary contactmembers 7 of the switch, and in separated relation to said members 7, apair of pivot lugs 8, in which i a branched lever 9 carrying at one endthe pair of movable {contact members 10 of switch mechanism, ispivotally mounted. The base plate 6 also carries a combined stop andguide bracket 11, to afford stop and guiding engagement for a slidingpush rod 12 that has operative connection with the lever 9 of themovable contact members 10. by means as follows Upon the push rod 12 andbetween the base plate 6 and the bracket 11, a collar 13 is'fixedlyattached, and has pivotal connection at anend of a spring toggle link14,

as shown. 'At the other end the toggle link 14 has a slidingand pivotedconnection to the end of the lever 9 aforesaid, at the end opposite tothe endof said lever which carries the contact members 10 of the switch.

The spring element 15 of the toggle link 14 has abutment at one endagainst a collar or cross pin 1 6, on the toggle link 14, and at itsother end against a like cross pin 17 carried on the lower end of thelever 9 aforesaid, and as. usual in many snap switch mechanisms ingeneral use, and with such springadapted to function in the ordinarymanner, to wit The spring element 15, is compressed: in

an initial movement of the movable contact carrying lever 9 in eitherdirection, and

then to complete its expansion and in a rapid manner the last portion ofthe movement of said lever to attain the usual snap action'in the makeand break movement of the switch mechanism.

In the construction shown, the push rod 12 receives an initial manualmovement in one direction to close the switch circuit, preferably bymeans of a separate headed plunger 18, slidably arranged in a wall ofthe inclosin housino' 1 inv ali ned relation with i the .pushrod 12 andwith its inner end havingfoperativecontact with the adjacent end of saidpush rod. A spring 19 is associated with the plunger 18 to return thesameto its normal. outward position after being pushed inward by hand ineffecting a closing of the circuit of the switch mechanism and thestarting up of the motor and associated parts of the'apparatus. V

By means of the described separated construction of the push rod 12, andplunger speed reducing gearing 22 with the power shaft of the motor 5,so that with a normal speed of said motor the cam or wiper arm 20 willmake a complete'revolution in a period of one 11111111136, more or less.The cam or wiper arm 20 is arranged in operative rela-v 'tion to the endof the push rod 12, opposite to the. end of the push rod in operative engagement with the carrying lever. 9 of the movable contact members.of'the switch and is adapted to engageand impart the heretoforedescribed initial movement to said push rod12, 1n the opening or circuitbreaking movement of the switch mechanism, in which the final movementof the parts is efiected by.

the s'pring toggle connections '14, 15, heretofore described.

A material part of this improvement consists in so mo-unting-the camor.wiper arm .20 on the countershatt21, so that the outer point or endof saidrcam or;wiper arm will not be left in the path of: thepush rod12,

,with .a stoppage oi the motor by the breaking ofits circuit. To suchend the hub of the cam or wiper arm 20 is loosely mounted meddling ormischieon a hub 23 fixed on the countershaft 21 in inoperative positionin the recess 25 and with said spring as the operative connectionbetween said hubs to attain a movement of the cam or wiper arm 20,during the inoperative portion of the revolution of said cam or wiperarm. Nhen, however, the active portion of such revolution begins, withthe active portion of the cam or wiper arm coming into operative contactwith the end of the push rod 12, tnefi Xed hub 23 will turn in advanceof the hub portion of said cam or wiper arm and bring the aforesaid stud24; into driving contact with an end of the elongated recess 25, so thatthe two hubs will complete their revolution in unison and in a positivemanner; During such portion of the revolution the cam or wiper arm 20effects the described initial opening move- 161113 of the switchmechanism. 7 r v With the outer point or end of-the cam or wiper arm 20reaching theend of the push rod 12, the spring; 26 is free todraw suchend or point of the cam or wiper arm out of the path of said'push rod,and restore the relation between the hub of the cam or wiper arm 20 andits carrying hub- 23, first set forth, ready for a succeeding cycle ofoperations of the apparatus.

Having thus fully described nay-invention,

what I claim a-nddesire to secure by'Let- .ters Patent, is

1. The combination in a time switch mechanism of the type described, ofa make ,and' break switch the movable member of which is of the snaptype, with the snap connection comprising a toggle link and springarranged intermediate of said movable member and-a. switch operativeelement, a push rod forming a part of the switch operating means andhaving operative connection with the movable switch member through thetoggle" link and spring aforesaid, a rotary cam having intermittentoperative "engagement with said push rod, and amotor driven shaftcarrying said cam and havingalternating operative engagement therewith,a

spring and a stud and an elongated recess constitutmg the means ofengagement.

v2. The comblnatlon 1n a time switch mechanism offthe typedescribed, ofa make and break switch. a pushrod operatively asis o- ,ciated withthemovable contact i'nembe of said switch, a rotary cam having intermittentoperative f engag'ement w thsaid push rod, a motor dr ven shaftvcarryingsa d cam and having'alter'nating operative engage- Inn ment therewith, aspring and a stud and an elongated recess constituting the means ofengagement, and a manually actuated spring plunger having pushengagement with said push rod, the stroke of said plunger being adivision of the normal stroke of the push rod.

3. The combination in a time switch mechanism ot' the type described, ofa make and break switch the movable member of which is of the snap type,with the snap connection comprising a toggle link and spring arrangedintermediate of said movable member and a switch operating element, apush rod forming a part of the switch operating means and havingoperative connection with the movable switch member through the togglelink and spring aforesaid, a rotary cam having intermittent operativeengagement with said push rod, a motor driven shaft carrying said camand having alternating operative engagement therewith, a spring and astud and an elongated recess constitutin the means of engagement, andmanually actuated spring plunger having push engagement with said pushrod, the stroke of said plunger being'a division of the normal stroke ofthe push rod.

4. The combination in a time switch mechanism, of an enclosing casing, acircuit controlling switch of the snap or sudden opening and closingtype, a rotary cam having a throw less than the extent of movement ofthe movable member of the switch and adapted for operative engagementwith the closing casing and having a throw less than the extent ofmovement of the movable member of the switch and adapted for operativeengagement with the movable member to effect a partial closingmovementof the same, the final opening and closing movements of the movablemember being of the sudden type under the influence of its operatingspring.

5. The combination in a time switch mechanism of an enclosing casing, acircuit controlling switch of the snap or sudden closing and openingtype,'a rotary cam having operative connection with the movable contactmember of the switch, said movable member having movement in arectilinear path, a motor driven shaft having operative engagement withsaid cam by means of a limited loose connection which includes as 3, arta spring tending to yieldingly maintain the cam in a forward position inrelation to the motor driven shaft.

6. The combination in a time switch mechanism of an enclosing casing,acircuit controlling switch of the snap or sudden closing and openingtype, a motor driven shaft, a circular hub fixed on said shaft, a ringcarrying a cam projection for operative connection with the movablecontact member of the switch, said ring being loosely mounted on theaforesaid hub with its independent movement limited by a stud andelongated slot connection between the parts, and a spring tending toyieldingly maintain said ring in an advanced position on said hub.

Signed at Vaukegan, Illinois, this 3rd day of June, 1925.

GEORGE A. BURGESS.

